//
//  ViewController.m
//  coreData
//
//  Created by dllo on 15/11/20.
//  Copyright © 2015年 蓝鸥科技. All rights reserved.
//

#import "ViewController.h"
#import "CoreDataManagerr.h"
#import "Student.h"
@interface ViewController ()
@property(nonatomic, strong)CoreDataManagerr *manager;
- (IBAction)add:(id)sender;     // 添加
- (IBAction)select:(id)sender;  // 查找
- (IBAction)update:(id)sender;  // 修改(更新)
- (IBAction)delete:(id)sender;  // 删除

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    self.manager = [CoreDataManagerr defaults];
    NSLog(@"url ========== %@",[self.manager applicationDocumentsDirectory]);
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

// coredata添加方法
- (IBAction)add:(id)sender {
    
    // 创建实体描述
    // 参数1:描述的实体
    // 参数2:数据管理器
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Student" inManagedObjectContext:self.manager.managedObjectContext];
    
    // 创建实体
    // 参数1:实体描述
    // 参数2:数据管理器
    Student *stu = [[Student alloc] initWithEntity:entity insertIntoManagedObjectContext:self.manager.managedObjectContext];
    stu.name = @"大脚";
    stu.age = @18;
    stu.sex = @"女";
    stu.hobby = @"男";
    stu.number = @12;
    
    // 交钱
    [self.manager saveContext];
    
}

// 查找
- (IBAction)select:(id)sender {
    
    // 获取查询数据的请求,相当于数据库的查询语句
    NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:@"Student"];
    // 添加约束 谓词
    NSPredicate *predicate = [NSPredicate predicateWithFormat:[NSString stringWithFormat:@"%@ == %@", @"name", @"%@"], @"大脚"];
    
    // 生成约束
    request.predicate = predicate;
    
    // 通过某个key给数组排序
    NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:YES];
    
    [request setSortDescriptors:[NSArray arrayWithObjects:sortDescriptor, nil]];
    
    NSError *error;
    
    NSArray *array = [self.manager.managedObjectContext executeFetchRequest:request error:&error];
    
    NSLog(@"%ld", array.count);
}

// 修改
- (IBAction)update:(id)sender {
    
    // 获取查询数据的请求,相当于数据库的查询语句
    NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:@"Student"];
    // 添加约束 谓词
    NSPredicate *predicate = [NSPredicate predicateWithFormat:[NSString stringWithFormat:@"%@ == %@", @"name", @"%@"], @"大脚"];
    
    // 生成约束
    request.predicate = predicate;
    
    // 通过某个key给数组排序
    NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:YES];
    
    [request setSortDescriptors:[NSArray arrayWithObjects:sortDescriptor, nil]];
    
    NSError *error;
    
    NSArray *array = [self.manager.managedObjectContext executeFetchRequest:request error:&error];
    
    Student *stu = [array lastObject];
    stu.sex = @"男";
    
    [self.manager saveContext];
}

- (IBAction)delete:(id)sender {
    

    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Student" inManagedObjectContext:self.manager.managedObjectContext];
    [fetchRequest setEntity:entity];
    // Specify criteria for filtering which objects to fetch
     NSPredicate *predicate = [NSPredicate predicateWithFormat:[NSString stringWithFormat:@"%@ == %@", @"sex", @"%@"], @"女"];
    [fetchRequest setPredicate:predicate];
    // Specify how the fetched objects should be sorted
    NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"sex"
                                                                   ascending:YES];
    [fetchRequest setSortDescriptors:[NSArray arrayWithObjects:sortDescriptor, nil]];
    
    NSError *error = nil;
    NSArray *array = [self.manager.managedObjectContext executeFetchRequest:fetchRequest error:&error];
    for (Student *stu in array) {
        [self.manager.managedObjectContext deleteObject:stu];
    }
    
    
    [self.manager saveContext];
    
    
  
}



@end
